The function of the adaptive immune system is largely mediated by lymphocytes (B and T cells) that express a diverse repertoire of immune receptors against virtually any foreign substance (Abbas et al., Cellular and Molecular Immunology, Edn. 6th. (Saunders Elsevier, Philadelphia; 2007); Murphy et al., Janeway's Immunobiology, Edn. 7th. (Garland Science, New York; 2008); Paul, Fundamental Immunology, Edn. 6th. (Wolters Kluwer/Lippincott Williams & Wilkins, Philadelphia; 2008)). In order to generate the repertoire of antibodies necessary for antigen recognition, each lymphocyte independently constructs a unique receptor through the process of VDJ recombination. Id. Each cell randomly selects a single V, D, and J gene segment through genetic recombination, introducing additional non-germline-encoded nucleotides at the junctions (FIG. 1). This process creates antibody diversity, the majority of which is encoded in the heavy chain complementarity determining region 3 (CDR3) (Rock et al. (1994) J. Exp. Med. 179:323; Xu and Davis (2000) Immunity 13:37). The complexity and dynamics of a single human immune repertoire have yet to be deeply probed, and the ability to track the repertoire dynamically has not been demonstrated in any organism.